Valve and a method of closing a valve

ABSTRACT

Valve ( 1 ) with a through-going axial bore ( 4 ), a first spindle ( 5 ) axially displaceable in the bore ( 4 ), an elastic/flexible seal ( 10 ) placed at the one end surface ( 6 ) of the first spindle ( 5 ), at least two hollow connection branches ( 7, 8 ), each of which connects the valve to an outer coupling, said first spindle ( 5 ) in a first position forming a first annular sealing surface ( 9 ) between the outer surface of the seal ( 10 ) and the inner bottom ( 11 ) of the valve body which contains the outlet opening ( 29 ), and where the first spindle ( 5 ) lies coaxially inside a second axially displaceable and hollow spindle ( 12 ) lying in the bore ( 4 ), the end surface of which or parts thereof ( 13 ) form a second annular sealing surface ( 14 ) between the outer surface of the seal ( 10 ) and the inner bottom ( 11 ) of the valve body at a second position radially from the first annular sealing surface ( 9 ). There is hereby achieved a valve whereby it is possible to take samples without any risk of contamination of the place at which the samples are taken, and thus ensure that the samples taken will be correct.

The invention concerns a valve with a through-going axial bore, a firstspindle axially displaceable in the bore, an elastic/flexible sealplaced at the one end surface of the first spindle, at least two hollowconnection branches each of which connects the valve to an outercoupling, said first spindle in a first position forming a first annularsealing surface between the outer surface of the seal and the innerbottom of the valve body, which contains the outlet opening. Theinvention also concerns a method of closing a valve.

From EP 468,957 a valve is known for the taking of samples, e.g. withinthe foodstuffs industry, where the bottling of milk, fruit juices andthe like is carried out, and where there is a need for anaseptically-sealing valve for the taking of the samples. Such an asepticseal is also suitable within, for example, the pharmaceutical industry.The above-mentioned patent publication discloses such a valve which canbe used for this purpose, but where between the spindle lying in thevalve housing and the bottom of the valve housing, a seating is formedsolely by closing against the container from which the sample is to beremoved. There hereby arises a risk that a contamination of the seatingoccurs, whereby bacteria can be transferred in connection with theactual taking of the sample, whereby the result of the sample-taking isnot correct.

It is thus desirable to provide a valve whereby it is possible to carryout the sample-taking without any risk of contamination occurring at theplace at which the sample is taken, and thus that the samples taken arenot incorrect.

This object is achieved with a valve of the kind disclosed in thepreamble, and also where the first spindle lies coaxially inside asecond axially displaceable and hollow spindle lying in the bore, theend surface of which or parts thereof form a second annular sealingsurface between the outer surface of the seal and the inner bottom ofthe valve body at a second position radially from the first annularsealing surface.

The manner in which the valve functions is thus that a double sealing isachieved between the spindles and the bottom, so that the outermostannular seating can be disinfected by steam being blown in through oneof the connection stubs when this outermost seating is not activated andwhen the first seating is activated, i.e. when the inner spindle is atthe bottom. This position will typically be held for a period of aminute, during which the disinfection takes place. Hereafter, the outerseating will be activated by the outer spindle moving to the bottom,whereby an annular sealing surface is formed around the annular sealingsurface of the first seating.

Hereafter, the inner spindle can be drawn back, whereby the innerseating is inactivated, after which a sample can be taken by the drawingback of the outer seating, in that the bacterial flora which is now onthe inner seating originates exclusively from the container in which thevalve is mounted, which means that the sampling which takes place willreflect the correct condition, and in that the outer seating, asexplained above, has been sterilised by means of the steam.

The spindles can be activated mechanically, but can also be activated bymeans of compressed air, where the controlling of this takes themovement pattern between the two spindles into account.

By providing a valve according to the invention and as further disclosedin claim 2 and 3, an expedient manner is achieved in which to bringabout the movement pattern between the first and second spindle.

By providing a valve according to the invention and as further disclosedin claim 4, it is avoided that the spindles execute a rotating movement,but exclusively execute the axial movement, which is of great importancewhen the spindles are at the bottom during the formation of both firstand second seating.

By providing a valve according to the invention and as further disclosedin claim 5 and 6, the possibility is achieved of activating the spindlesmechanically.

By providing a valve according to the invention and as further disclosedin claim 7 and 8, it is achieved that the two seatings are well-definedand with a well-defined separation.

The invention also concerns a method as disclosed in claim 9 and 10, bywhich method it is achieved that there does not occur a transfer ofbacteria between the samples which are taken.

The invention will now be explained in more detail with reference to thedrawing, where

FIG. 1 shows a valve according to the invention shown in section, whereboth seatings are inactive,

FIG. 2 shows the valve shown in FIG. 1, where only the innermost seatingis active,

FIG. 3 shows the valve shown in FIG. 1, where both the outer seating andthe inner seating are active,

FIG. 4 shows the valve shown in FIG. 1, where only the outer seating isactive,

FIG. 5a is a sectional view of the outer spindle,

FIG. 5b shows the periphery of the outer spindle, where the slots aredisposed and in unfolded perspective,

FIG. 6a shows a sectional view of the inner spindle,

FIG. 6b shows the periphery of the inner spindle, where the slots aredisposed and in unfolded perspective, and

FIG. 7 shows a sectional view of the auxiliary housing.

FIGS. 1-4 show an example embodiment of a valve 1 seen in section, whichcomprises a valve housing shell 2 connected with bolts to a valve body3. The valve housing shell 2 and valve body have a bore 4 in theircenter axis, and in which bore there is disposed a solid first spindle5, said first spindle 5 being axially parallel with the bore 4, andwhere said first spindle 5 lies in a hollow second spindle 12 which isaxially parallel with the remainder. The spindles are axially moveablein the bore.

The valve 1 further comprises preferably two connection stubs, a firstconnection branch 7 and a second connection branch 8 lying diametricallyopposite to the first connection branch 7, and which are possiblyconnected to an element for the taking of samples, for example a bottlewhere the one is concerned, and where the second is concerned to e.g.steam which is blown in for the disinfection of the valve.

When the spindles are in the bottom position, an annular passage ishereby formed between the two connection branches 7, 8.

Between the spindles and the valve housing shell 2 there is provided anauxiliary housing 21, the inner surface of which is congruent with theouter surface of the second spindle 12. Opposite this auxiliary housing,and at the end surfaces 6, 13 of the first and second spindles, there ismounted a seal 10 of a flexible and elastic material, which seal canform a sealing closure between the spindles on the one side and theoutlet opening 29 of the valve 1 on the other side, which outlet opening29 lies in the bottom 11 of the valve body and is parallel with the axisof the bore.

Under the lower end edge 25 of the auxiliary housing there is mounted abush 26, under which a coil spring 24 is inserted coaxially with thefirst and second spindle.

FIG. 1 shows the case in which both spindles are at a maximum distanceaway from the opening 29, whereby there is free passage between thestubs 7, 8 to the valve opening 29.

FIG. 2 shows activation of the first spindle 5, which is pressed to thebottom, whereby the valve seal 10 lies up against the bottom 11 of thevalve body and forms a first seating 9 which is an annular sealingsurface surrounding the valve opening 29. Hereafter, the second spindle12 is activated, this being a hollow cylinder in which the first spindleis disposed, and where by an axial movement said second spindle ispressed with its end surface against the bottom 11 of the valve body,whereby the seal which surrounds this spindle is pressed against thebottom 11 of the valve body and forms a new annular sealing surface,designated the second annular sealing surface 14, which lies in a radialmanner to the first. This is shown in FIG. 3. Between these two sealingsurfaces thus formed, the seal is expediently provided with a groove 27,whereby a well-defined demarcation of the two seatings takes place. Theseal can be configured as a membrane, for example as disclosed in EP468,957. The seal can also be effected by two O-rings or the like lyingcoaxially.

The seal/membrane ensures that there is a tight closure towards the restof the valve in the area over the two connection branches 7, 8.

FIG. 4 shows the situation where the first spindle 5 is drawn back,whereby the first annular sealing surface 9 is inactivated, and wherebythere is only the second annular sealing surface 14.

As shown in FIGS. 5-6, the movement pattern between the two spindlesarises by said spindles being provided with both vertical and helicalslots/recesses. At the upper end and opposite that end at which the sealis placed, in the wall of the outer spindle 12, which is configured as acylinder with walls of 1-2 mm, there is formed a through-going slot 16with a breadth of a few mm, and which slot extends in a slightly helicalmanner, in the sense that the first third part of the slot in theunfolded plane extends at a slight angle upwards, corresponding toapprox. 5° to the horizontal plane. Thereafter, for the next third partthe slot extends horizontally, and for the last third part it anglesdown towards the seal forming an angle of approx. 20° to the horizontal.The way in which this slot extends is shown in FIG. 5b, where thespindle is “folded out”. This section also shows the slot 18 extendingvertically from the upper end edge, and at a distance from thiscorresponding approx. to the lower end of the helical slot.

The corresponding slot 15 in the inner spindle is seen in FIG. 6b, thewall of this spindle similarly comprising a slot with a length whichextends for approx. ¾ of the periphery of the spindle and with a depthin the solid spindle of approx. 1-2 mm. Unlike the slot in the outerspindle, this slot extends in another manner, in that the first thirdpart extends horizontally, the next third part extends at a slight angleto the horizontal and downwards towards the seal corresponding toapprox. 5°, and where the last third part angles down more sharplytowards the seal and corresponding to approx. 15-20° to the horizontal.Moreover, in this spindle there is also a vertically-extending slot 17with the same length as that seen indicated in the outer spindle.

The object of the vertical slots is to ensure that the spindles do notdescribe a rotating movement with their axial movements. With referenceto FIG. 2, the axial movement is brought about by the helical slot 15 inthe inner spindle being connected by a pin to the corresponding helicalslot 16 in the outer spindle, said helical slot 16 in turn beingconnected to the auxiliary housing 21 where the pin is possibly ledthrough a circular hole 22. The pin does not extend through the valvehousing shell, and is a loosely-mounted pin. On the opposite side, asecond pin 20 is placed in a vertical slot and engages in the verticalslot 17 in the inner spindle, in the vertical slot in the outer spindle18 and finally in the horizontal slot 22 in the auxiliary housing 21,which also comprises a vertical slot 23. The pin is fastened to thevalve housing shell 2, or extends through this, in that the pin can beformed as a screw.

The auxiliary housing 21 has a cylindrical rod 30 which extends inextension of the axis of the bore and protrudes out of an opening in thevalve housing shell 2, and when a turning of the auxiliary housing 21 iseffected by the turning of a knob 31, these forces will be transferredvia the pins to both the outer and the inner spindle, which due to themutual positioning, dimensions and angles of the slots will describe themovements indicated in FIGS. 1-4, and where the vertical slots ensurethat no rotation takes place between the two spindles, but exclusivelyaxial movements.

The movement pattern between the two spindles can also be brought aboutby means of compressed air which is activated by a control mechanismwhich ensures the desired movement pattern. In this case the spindlesare not configured with slots, and the auxiliary housing becomessuperfluous. In this case it is important that tight seals are providedbetween the individual components.

The valve 1 will thus be mounted with its valve body 3 on the containerfrom which a sample is desired to be taken, and where the valve willeffect a closure out towards the outside. A sample will be taken via oneof the connection stubs, and a disinfection of the interior of the valvewill be effected via the second connection stub, preferably by means ofsteam. The starting point for the use of the valve will thus be FIG. 1,which shows the valve inactive with free communication to the inside ofthe container.

FIG. 2 shows how the inner seating 9 is activated and effects aclosing-off of the insides of the container. In this position, theannular sealing surface 14 can be disinfected by the spraying-in ofsteam. This position will typically be held for approx. one minute.Thereafter, the sealing surface 14 can be activated, whereby aclosing-off of the inner sealing surface 9 or first seating takes placeas shown in FIG. 3.

Finally, as shown in FIG. 4, the inner spindle is brought to the drawnback position, whereby there is a free inwards communication. Hereafter,the inner and the outer spindles are brought into their most withdrawnpositions as shown in FIG. 1, and whereby it is now possible for thesample to be taken, and this sampling is not contaminated in that theouter seating has had the inner seating closed-off, and in that theinner seating has been active during the sterilisation of the outerseating, which means that no transfer of bacteria occurs from the takingof one sample to the taking of the next.

FIG. 7 shows a sectional view of the auxiliary housing 21, in whichthere is a vertical slot 23 which in length corresponds to the spindleslots, and an annular, through-going slot 22 in the wall and extendingfor approx. ¾ of the periphery, and which lies at the same level all theway around.

What is claimed is:
 1. A valve (1) comprising: a through-going axialbore (4); a first spindle (5) axially displaceable in the bore (4); anelastic/flexible seal (10) placed at one end surface (6) of the firstspindle (5); at least two hollow connection branches (7,8) forwithdrawal of samples, each of which connects the valve to an outercoupling; said first spindle (5) in a first position forming a firstannular seating surface (9) between the outer surface of the seal (10)and an inner bottom (11) of the valve body which contains an inletopening (29) from which samples are drawn into the valve; the firstspindle (5) lies coaxially inside a second axially displaceable andhollow spindle (12) lying in the bore (4); and the end surface of thesecond spindle or parts thereof (13) forming a second annular seatingsurface (14) between the outer surface of the seal (10) and the innerbottom (11) of the valve body at a second position radially spaced fromthe first annular seating surface (9).
 2. Valve according to claim 1,characterised in that the surface of the first spindle (5) is configuredwith an outer annular slot (15) for approx. ¾ of its periphery.
 3. Valveaccording to claim 1, characterized in that approx. ¾ of the wall of thesecond spindle (12) is configured with an annular slot (16), said slot(16) extending through the wall, and in that a loose pin (19) is placedin the slot (16) and engages in the slot (15) in the first spindle. 4.Valve according to claim 1, characterized in that the first (5) and thesecond (12) spindle are each configured with a vertical slot (17, 18),said vertical slot (18) in the second spindle extending through thewall, and in which slot a pin (20) is placed, said pin (20) being infirm connection with the valve housing shell (2) of the valve (1) andengaging in the slot (17) in the first spindle via the slot (18) in thesecond spindle.
 5. Valve according to claim 1, characterized in that anauxiliary housing (21) is mounted between the valve housing shell (2) ofthe valve and the second spindle (2).
 6. Valve according to claim 1,characterized in that a helical spring (24) is inserted coaxially withthe first (5) and second spindle (12).
 7. Valve according to claim 1,characterized in that the seal (10) between the first (9) and secondseating (14) is configured with an annular recess/groove (27).
 8. Valveaccording to claim 6, characterized in that the seal comprises twocoaxial O-rings.
 9. The valve of claim 1, further comprising: the firstand second spindles being selectably operative to: an open state inwhich both spindles are moved to respective open positions in which theouter surface of the seal (10) is withdrawn from the first (9) andsecond (14) annular seating surfaces, whereby a sample is taken from theinlet opening (29) and communicates to one of the connection branches(7,8), a cleaning state in which the first spindle (5) is moved to aclosed position to engage the seal (10) with the first annular seatingsurface (9) while the second spindle (12) remains at the open positionwith the seal withdrawn from the second annular seating surface (14),whereby the second annular seating surface (14) remains exposed todisinfection by introducing a disinfecting fluid through one of theconnection branches (7,8); a transition state in which the secondspindle (12) is moved to a closed position to engage the seal (10) withthe second annular seating surface (14) while the first annular seatingsurface (9) remains closed, whereby the disinfected second annularseating surface (14) remains uncontaminated; and to a closed state inwhich the first spindle (5) is moved to the open position in which theseal (10) is withdrawn from the first annular seating surface (9) andthe second spindle (12) remains at the closed position, whereby theinlet opening (29) is open to sample material while the second annularseating surface (14) remains closed to the connection branches (7,8).10. Method for the closing of a valve with a through-going axial bore, afirst spindle axially displaceable in the bore, an elastic/flexible sealplaced at the one end surface of the first spindle, at least two hollowconnection branches for withdrawal of samples, each of which connectsthe valve to an outer coupling, said first spindle moving in an axialmovement towards the bottom of the inner body of the valve in bringingabout a first position, in which position a first seating forms anannular sealing surface between the outer surface of the seal and theinner bottom of the valve body which contains an inlet opening; and asecond spindle, in which spindle the first spindle is disposed, thesecond spindle being movable downwards into its bottom position by anexclusively axial movement for the formation of a second seating in asecond position; comprising the steps of: operating the valve to an openstate in which both spindles are moved to respective open positions inwhich the outer surface of the seal is withdrawn from the first andsecond annular seating surfaces, whereby a sample is taken from theinlet opening and communicated to one of the connection branches,operating the valve to a cleaning state in which the first spindle ismoved to a closed position to engage the seal with the first annularseating surface while the second spindle remains at the open positionwith the seal withdrawn from the second annular seating surface, wherebythe second annular seating surface remains exposed to disinfection byintroducing a disinfecting fluid through one of the connection branches;operating the valve to a transition state in which the second spindle ismoved to a closed position to engage the seal with the second annularseating surface while the first annular seating surface remains closed,whereby the disinfected second annular seating surface remainsuncontaminated; and operating the valve to a closed state in which thefirst spindle is moved to the open position in which the seal iswithdrawn from the first annular seating surface and the second spindleremains at the closed position, whereby the inlet opening is open tosample material while the second annular seating surface remains closedto the connection branches.